Which statement is false?

Which statement is false?

Cost of well$-$in$-$progress is included in Wells and Equipment under successful efforts $($SE$).$

Wells and Equipment are amortized based on proved developed reserves under SE$.$

A barrel of oil is measured at a standard temperature of $60$ degrees Fahrenheit.

In the unit$-$of$-$production formula, the book value at year end is used.

In practice the most commonly used cost center is a field under SE$.$